It seems very safe, given the slow speed. If someone falls off, and falls over, it will be a sideways fall, likely a fall off the bike. If the bike or the person then forms an obstruction, people further down the Trampe can pull their foot off. stand on the curb, and then either walk or bike up the hill, likely (though this might vary depending on local) first helping the person who fell.

The very precariousness of resting your foot on a small metal plate would seem to improve the safety of the device, since there's very little that could catch and drag someone, which is an issue of concern with any automated people mover.

I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.